Intramolecular addition reactions of carbonyl ylides formed during photocyclization of aryl vinyl ethers
                                
                                    
                                        作者:James P. Dittami、Xiao Yi Nie、Hong Nie、H. Ramanathan、Scott Breining、Jon Bordner、Debra L. Decosta、Jeffrey Kiplinger、Philip Reiche、Richard Ware                                    
                                    
                                        DOI:10.1021/jo00019a020
                                    
                                    
                                        日期:1991.9
                                    
                                    Photocyclization of aryl vinyl ethers reportedly proceeds via carbonyl ylide intermediates.  The photochemical behavior of several aryl vinyl ethers, which incorporate a pendant alkene side chain, was explored.  Naphthyl vinyl ethers 1c and 1d provided products that are consistent with photocyclization and subsequent intramolecular ylide-alkene addition.  Product distribution is influenced by solvent and temperature effects.  Thus, irradiation of 1c in toluene provides 9a in 87% yield.  However, irradiation of 1c in methanol/toluene (1:1) provides 3c (45%), 11 (24%), and 12 (23%).  Product 12 results from photoinitiated intramolecular [2 + 2] cycloaddition of the butenoate ester side chain to the naphthalene system.